1. Field of the Invention
This invention relates to pipeline inspection tools, and more particularly to apparatus and methods for linking sensors or inspection assemblies in an in-line inspection tool.
2. Background Art
Pipeline inspection tools, commonly called “smart pigs,” have been used for the last half-century or more to determine the condition of pipeline by examining it from the interior of the pipeline. Such tools use a variety of inspection technologies including mechanical geometric examination, ultrasonic inspection of several types (UT), eddy current examination, magnetic flux leakage technology (MFL), electromagnetic acoustic transducer (EMAT) technology and others. These tools use instrumentation of diverse types to introduce a measurement field and sensors to collect data from the field. The base instrumentation and the sensors are mounted to an inspection tool and contact the inside of the pipe wall either directly by the instrumentation itself or indirectly through supporting or coupling arrangements. This contact must be compliant to allow inspection devices or their supporting structure to connect with the wall even when the inside shape of the pipeline may change due to intruding features or pipe wall damage. That contact may prevent the inspection tool from moving in a reverse direction without damaging the inspection devices or other parts of the inspection tool. All known inspection technologies require this contact or coupling and conventional inspection tools are generally incapable of moving in a reverse direction without damage.
The apparatus disclosed herein provides an improved pipeline inspection tool.